Polymerization of olefins



Patented'oct. 26,1948

. 2.45am I eonrmamza'non or OLEFJINS atom M. Drexel mu, m Stanford a. lletzel. Cheltenham, Pa salmon to Sun Oil Company, Philadelphia, Pa. a corporation of I New Jersey I No Drawing. Application mm- :0, i945,

I smn No. 625,094

This invention relates to the polymerization of normally gaseous hydrocarbons, particularly hy-' drocarbons having three or more carbon atoms and at least one double bond or oleilnic linkage per molecule, employing a novel solidcatalyst per mitting the use of advantageous operating conditions, for exampla materially lower pressures.

According to the invention normally gaseous olefins, particularly hydrocarbons havingthree or more carbon atoms and at least one double bond or olefinic linkage per molecule are polymerized under conditions hereinafter described in presence of a solid polymerization catalyst comprising essentially silica gel, alumina and nickel.

In one embodiment the present invention comprises a process for the polymerization of the normally gaseous ole'flins comprising propylene and butylenes present in hydrocarbon gases, resulting from cracking or other refinery operations, for 'the production of compounds, suitable for further processing into a fuel for an internal combustion or other engine, by subjecting said olefin hydrocarbons to polymerization conditions of time, temperature and pressure hereinafter described in presence of a polymerization catalyst comprising essentially slica gel, alumina and nickel.

In a further embodiment the process of the present invention can be employed to effect the polymerization of other olefins. such as monoolefins of higher molecular weight etc in the presence or absence of propylene and butylenes or other hydrocarbon gases. 1

According to the invention the catalyst employed is prepared by impregnating slica gel particles, of size desired, with a water or other solution of aluminum and nickel salts. In one method of preparation solutions of aluminum and nickel nitrates of desired concentrations were added to a known quantity of silica gel, of desired particle 4 size, in an evaporating dish. The mixture was Joanne. (oi. zoo-start) A catalyst having an approximate composition of 98% slica gel, 1% alumina and 1% nickel was prepared by adding one liter of an aqueous soluti'on containing 97 grams of nickel nitrate Ni- (NO:)2.6H2O, and 75 grams of aluminum nitrate, Al(NOa)a.9H2O, to 2 kilograms of silica. gel in an evaporating dish. The mixture was evaporated to dryness; with stirring, and then ignited for about nine hours to convert the nitrates to their respective oxides. Prior to use the catalyst mass was charged into a catalyst tube and ignited for one hour with air at'400" C. to ensure complete conversion to the oxides and to remove traces of water, It was then reduced with a slow stream of hydrogen for about nine hours at 406 0. to convert the nickel oxide to nickel.

,While simultaneous impregnation with aluminum and nickel'nitrate has been described it will be apparent to those versed in thecatalyst art that other methods for preparation of the composition of the invention can be employed, although that described is presently preferred.

Also, for starting materials in the preparation of the catalyst composition any compound of aluminum, which upon ignition will. yield alumina in activated form upon silica gel, and nickel salt,

I which will yield nickel oxide on ignition and which can be subsequently reduced to nickel on the silica gel can be employed, the essence of the invention insofar as it relates to the catalyst composition being in the specific combinations of materials as I set forth.

evaporated to dryness, with stirring, and then ig- 5 nited for about eight to ten hours or until the salts were completely decomposed. This was followed by reductionwith hydrogen at elevated temperature.

According to the invention the catalyst composition is, by weight so a-99.98% silica gel, 0.0l%-10% alumina and 0.01 %-10% nickel. .Good results have been obtained with catalyst'composition 90%-99% silica gel,- /z%-5% alumina and /z %-5% nickel, A catalyst having a composition of about 96 silica gel, about 2% alumina and about 2% nickel has been employed as will appear hereinafter.

For example, freshly precipitated aluminum hydroxide can be admixed with nickel hydroxide and added to silica gel and the whole ignited and then reduced as set forth previously. Or, if desired an aluminum compound and a nickel compound can be distributed on silica gel and the entire mass ignited in air followed by reduction of the ignited mass. As stated, other methods of preparation, apparent to those versed in the art can also be employed; In the catalyst composition above described, cobalt may be substituted for the nickel.

It appears that advantageous results can be obtained when employing a composition containing less alumina than nickel. While the quantity of alumina should be substantially smaller than that of nickel it is absolutely necessary that an appreciable quantity of alumina be present.

The period of activity of the catalyst will naturally vary with circumstances of its use. In the polymerization of oleflnic hydrocarbons, tests have shown that a practical conversion can be obtained for periods up to 5 hours without regeninafter.

eration. The catalyst can be regenerated many times to substantially its original activity. After seventy-five regeneraticns, tests have shown that the activity was essentially unchanged.

In co-pending application Serial No. 025,002, filed October 30, 1900, by the'instant inventors,

- there is described and claimed a catalyst composition consisting by weight of sea-eases silica gel. 0.01%-% alumina and 0.01 90-10% nickel.

Also. in co-pending application Serial No. 620,-

008, filed October 80, 1940, by the instant inventors, there is described and claimed a process for the polymerization of ethylene employing a catalyst consisting essentially of silica gel. alumina and nickel or cobalt: while application Serial No.

742,183, filed April 17, 1944, by the instant inven- When polymerizing propylene and butylsnes, or other gases, the charging rate, or time of contact. will preferably be such as to allow these gases to remain in contact with the catalyst for-a time sufficient to cause the desired degree of conversion. Charging rates of 1 gram-12 grams gas/per "together a temperature within the range of 200' (ii-400' 0., preferably 200' 0.400 0.. can be employed.

It is to be understood that temperatures outside these ranges are not excluded from the scope of the invention.

The pressure employed for the polymerization of propylene and the butylenes will depend upon whetherthese are to be polymerized separately or in combination with each other in the presence or absence of other hydrocarbons. If substantially pure propylene is to beconverted a pressure in the range lira/sq. in.-150 lbs./sq. in.. preferably in the range of so lbs./sq. in.-100 lbs./sq. in.. can be employed. If normal butylene is to be polymerized a pressure in the range of 00 lbs/sq. in.-2oo lbs./eq. in., preferably in the range '00 lbs./sq. in.-1o0 lbs/sq. in., can be employed. 1f

isobutylene is to be separately polymerized a pressure within the range 80-lbs./sq. in.-250 lbs./sq. in., preferably 00 lbs./sq in.-l00 lbs/sq. in., can be employed.

If the foregoing gases are to be polymerized together a pressure in the range 30 ibs./sq. in.- 250 lbs./sq. in., preferably in the range lbs/sq. in.-160 lbs.'/sq..in., can be employed.

It is to be understood that pressures outside the foregoing pressure ranges can be employed but these are not. at present. preferred. Pressures from about atmospheric pressure to about 1,000 lbs/sq. in. are not excluded from the scope of the invention.

The following table shows results obtained according to the invention:

wmggg gi ram, Weight Per om Gas Charging 'lem Pressure. Polymerised Rate lbnlsq. in. Dimer 'lrimer, etc. higs silica gel alumina nickel single pass recycle single pass recycle 04.0 1 I 4.5 Pro ylene... .0250 400 so 0.0 10.4 0.7 n: I sec 94.6 I .5 .-...d0 .Olm 400 00 13.2 36.! 8.1 35.1 60.2 as i p 1 Butane-2 .0022 300 00 24.3 01. 0 13.3 M. 0 so. 8 0c 2 2 ...do .0010 000 00 14.0 03.3 7.4 82. 2 71.1 00 c 6 .do .0432 s00 00 9. c 47. ii a. 0 40.0 50.0 00 b 5 Butane-l .0300 300 00 7. i 37. 4 i0. 7 cc. 3 s1. 0 91. 5 1. 0 4. 6 sobutone 0370 300 6O 2!. 8 50. 2 N. 5 33. 3 50. 0 00.0 1.0 1.0 intone-2..-. .0828 300 250 30.0 81. 0 67.0 04. ll l. 0 4. 5 lsobutcne. .1270 300 200 is. 0 142.5 77.0

i Grams gas/minJgl-am catalyst.

minute/per 100 grams of catalyst have been employed. It is, however, within the scope of the invention to employ lower or higher charging rateswith or without recycling of any incompletely reacted gases. For example, incompletely reacted or unreacted gases can be treated in subsequent zones wherein an identical catalyst is employed. Or. if desired. the composition of the catalyst may be different. but within the ranges claimed herein, in said zones.

The temperature employed for the polymerization ofpropylene and the butylenes will depend upon whether these gases are to be polymerized separately or in combination with each other in the presence or absence of other hydrocarbons. I: substantially pure propylene is to be converted a temperature in the range of 300 C.-400 0.. preferably about 325 C.-375 C. can be employed.

If normal butylene is to be polymerized a tem- A distinct advantage of the invention is that certain compounds not heretofore polymerizablc to a substantial extent can be polymerized in good yield. For example. it has been found,

' unexpectedly, that alpha and beta butylenes in the absence of lsobutylene can be substantially polymerized. The prior art yield has been due largely to the polymerization of isobutylene or to the polymerization of alpha and beta butyienes in the presence of isobutyienes.

The polymerization of the gases according to I this invention can be effected employing recycling of any unreacted gases.

A series of conversion or polymerization zones can be employed inseries or in parallel. Each zone may be alternately used to polymerize gases or for the regeneration of the catalyst therein. The catalyst may be circul ated through the polymerization zone. or zones.

according to methods within the skill of those versed in the art.

Various modifications within the scope of the invention as defined herein and in the claims will be obvious to those skilled in the art.

The polymerization of oleilns containing three or more carbon atoms per molecule may also be effected, under conditions as hereinbefore described, by means of a catalyst composition similar to the present catalyst but which contains chromia in place of alumina. Such polymerization is not herein claimed as it forms the subject matter of our divisional application Serial No. 742,194, filed April 17, 194:7,

We claim 1. A process for the polymerization of oieflns containing three or more carbon atoms per molecule which comprises contacting the claims under polymerizing conditions with a catalyst consisting byweight of 80%-99.98% silica gel,0.01%-'10% i alumina and 0.01 of a metal selected from the group consisting of nickel and cobalt.

2. A process for the polymerization of propylene which comprises contacting propylene at a temperature within 300 C.-400 C. and at a pressure within 30 lbs./sq. in.-150 lbs/sq. in. with a cata-- lyst consisting by weight of 80%-99.98% silica gel, 0.01%-10% alumina and 0.01%-10% nickel.

3. A process for the polymerization of n-butylene which comprises contacting-n-butylene at a temperature within 250 C.-400 C. and at a pressure within 30 lbs/sq. in.'-250'lbs./sq. in. with a catalyst consisting by weight.of' 80%-99.98% silica gel, 0.0 l%-10% alumina 'and 0.01%10% nickel. u

4. A process for the polymerization of i-butyl- I ene which comprises contacting i-butylene ata temperature within 200 0-400 C; and at a pressure within 30 lbs./sq. in.-250 lbs./sq. in. with a containing threeoi' more carbon atoms per molecule which comprises contacting the olefins under polymerizing conditions with a catalyst consistcatalyst consisting by weight of %-Q9.9B% silica gel, 0.01%-10% alumina and 0.01%-10% nickel. 5. A process for the polymerization of oleflns temperature within the range 200 C. -400 C. with a catalyst consisting by weight of %-99% silica gel. %%5% alumina and /z%5% nickel, said catalyst having been prepared by adding aluminuns and nickel nitrates in aqueous solution to silica gel, evaporating and igniting the mass andignited mass. 4 ROBERT M. KENNEDY. STANFORD J. HETZEL.

, REFER NCES crrm) then reducing the The following references are of record in the "file of this patent:

UNITED STATES PATENTS Number Name Date 2,129,649 Crass et al. Sept. 13, 1938 2,332,276 Stahly Oct. 19, 1943 2,380,358 Anderson et al. July 10, 1945 Bailey et al Aug. '7, 1945 

